Hemo bioscience ELUclear is a glycine acid red cell elution kit. Its intended use is to dissociate (elute) IgG antibodies from red cell membranes so that they can be identified using standard serological techniques. The kit consists of an eluting solution with a pH indicator, a buffering solution and a concentrated wash solution which minimizes early dissociation during the wash phase.

The eluting solution and buffering solution are supplied in color coded dropper vials for ease of use and to help prevent contamination. For added convenience, we supply a wash bottle in every kit that is used to dilute the wash concentrate. Eluates prepared from the ELUclear kit have been tested and validated using both traditional tube and MTS gel* technologies.

Features

• Clearly defined endpoint color change
• Eluate has been tested and validated with tube and gel techniques
• Dropper pipettes supplied to prevent contamination
• Color coded reagent containers eliminate confusion and are easy to use
• Wash bottle with fill line allows easy preparation of working wash solution

*MTS gel is a registered trademark of Ortho Clinical Diagnostics Inc.

What is an elution and why is it done?

Elution is defined as the disassociation of IgG antibodies bound to the surface of red blood cells.

Red blood cells coated with IgG antibodies in vivo could indicate¹:

• Hemolytic Transfusion Reaction (HTR)
• Hemolytic Disease of the Fetus and Newborn (HDFN)
• Drug-Induced Hemolytic Anemia

Since the purpose of performing an elution is to identify these antibodies, the disassociation method used must not destroy or denature the antibodies. There are various techniques for accomplishing this disassociation, with the Glycine Acid technique being a quick and simple method which also provides adequate recovery of most clinically significant antibodies. The Hemo bioscience ELUclear Kit provides a convenient, standardized Glycine Acid elution method.

How does the Hemo bioscience ELUclear Kit work?

A sample of IgG coated cells is washed using a working wash solution prepared from ELUclear Concentrated Wash Solution, which is designed to remove any unbound antibody while maintaining the association of antibody bound to the cells.

The washed cells are then suspended in ELUclear Eluting Solution, a low pH glycine solution, to disassociate the antibody from the red blood cells. The suspension is centrifuged and the supernatant eluate, which contains the antibodies, is separated from the red blood cells.

Since the pH of the eluate is too low for accurate testing by routine methods, ELUclear Buffering Solution is added to adjust the pH. Bromcresol Purple is a pH color indicator which has been added to the eluting solution; a blue color indicates that the pH has been adjusted correctly and the eluate is now ready for antibody identification testing.

What methods can be used for testing eluates?

Eluates prepared using the Hemo bioscience ELUclear Kit have been tested and validated using traditional tube Indirect Antiglobulin Testing (IAGT) techniques as well as manual gel / column agglutination IAGT methods.

Although the use of potentiators such as Bovine Serum Albumin (BSA) or Low-Ionic Strength Saline (LISS) additive is unnecessary, the use of a polyethylene glycol enhancement additive (i.e. HBS-Peg 8000) has shown increased sensitivity of eluate testing for early alloimmunization detection².

References:
¹ Roback, JD, ed. Technical Manual. 16th ed. Bethesda MD: AABB 2008.
² Combs MR, Telen MJ. Testing eluates in Polyethylene glycol (PEG): A sensitive technique for detecting early alloimmunization. [Abstract] Transfusion 1989; Supplement 58S.